Pitch-coking process



2 Sheets-Sheet Filed Aug. s1, 192i May 2s, 1929.-`

;Ii.r

Patented -May 28A, 19729,A i

UNITED ASTATI-:s

PATENT OFFICE.

HEINRICH KOPPERS, F ESSEN-EUHR, GERMANY, ASSIGNOR TO THE KOPPERS DE-VELOPMENT CORPORATION, vOF PITTSBURGH, PENNSYLVANIA, A' CORPORATION 0FPENNSYLVANIA.

rrreH-coxme rnocnss.

i Application filed August 31, 1921. Serial No. 497,378.

A The invention relates toa` process of coking pitch, for the productionof substantially pure carbon suitable for electrodes and other usefulpurposes.

The coking of this substance has presented serious difficulties arismgmamlyl from the boiling ,and foaming o f the body of pitch whensubjected to the necessary coking heat in the retort, so that it wouldleak vout past the retort doors or covers and rise up and clog orobstruct the gas passages leading. from the upper part of the retort.Also the introduction of the pitch to be coked in a comparatively largebody into the' highly heated retort, as heretofore produced,

caused a chilling of the retort which resulted in the scaling oil' ofthe surfaces so exposed to heating and cooling, and also caused an undueexpansion and contraction of the retort as a whole, the opening of thecracks between the bricks, and the dropping out of thesilica cement, andfrom one or allof these causes the retorts were rapidly deteriorated andinjured, and silica as an objectionable 'impurity became mingled withthe resulting coke, rendering the latter unsuitable for the intendeduses of the saine. My invention obviates these difficulties byperforming theA coking of the pitch continuously, with a correspondingcontinuous in- -troduction'of the pitch in relatively small quantitiesat a time into the highly heated retort so that the chilling effect isso small, at any time, compared with the extent of the retort and thehigh heat. of the same that the described injuries cannot result.Nevertheless thepitch is fed into the retort with suiiicient rapidity sothat a body of sub1 stantially pure coke in quantity equal to the 40capacity of the retort is produced without undue expenditure of time.

A pitch-coking retort ,of relativelyI large horizontal extent inproportionto the depth of the cooler liquid portion of the pitch i whichexists in the retort at any time is used for the process, so that anextensive surface of the pitch is exposed to receive thecontinuouslyincoming additional pitch, and the Yrelatively cool pitch will touch thewalls of the retort for a very small depth, so that the chilling effectis negligible. Also there is an extensive horizontal surface of pitch togive iii freely the distillinggases without excit ing bubbling yorfoaming or not to any considerable degree.

' In accomplishing these useful results there is employed by preferenceva pitch-coking oven substantiallysuch asis shownlin the accompanyingdrawing, but this particular construction of oven is ,shown for thepurpose of'. illustration and explanation, and is not to limit theinvention tothe details of such construction, which may be variedwithout departure from the invention. In said drawings Figure 1 is avertical cross section of the pitch-coking oven embodying the invention,

on line I-I of Fig. 2.

Fig. 2 isa longitudinal vertical section of the same online II-II ofFig. 1.

Fig. 3 is a front end view of the same, the oven door being removed.

Referring to the drawings, 1 indicates the oven structure, generally,the same being built of suitable material, and the upper parts which areto be subjected to high degrees of heat being composed of refractory`material such. as silica :bricks or the like.

The lower part of thestructure comprises regenerator chambers 2, 3, 4and 5 which have the usual air and gas exits upward to the retort andlwhich are to be used in the known alternating manner, so that. the airand gas are heated tothe combustion point.

in thepreviously used regenerator chambers and the products ofcombustion pass down through and heat the regenerator chambers whichiarenext to be used for the incoming air and gas. v

I n the upper part ofthe oven is constructed the retort 6 which is of anarched contour nteriorly and is extended horizontally and sidewise toprovide for the above described large superficial4 extent of thegradually introduced pitch. The lining 7 ofV this. retort is madeof`si1ca brick andl is highly refractory or suiciently so for the cokingheat to be raised.`

After this retort has been heated tol the degree requisite .for cokingpitch. the latter is introduced in a small stream through the .pipe 8,which is arranged at one end near the top of the retort, and thestream'of liquid pitch is preferably caused to be of such force thatitwill be delivered or fall at a point a/bout midway between the two..ends of -the retort. The gaseous matter resulting from.

the coking operation passes outward from the retort through the pipe 9.

In performing the said coking with this apparatus the retort is firstraised to coking heat and until the limit of expansion has beensubstantially reached, and the liquid pitch -is introduced as rapidly asmay be under the condition that it must be raised to the 'cokingtemperature without having any injurious chilling effect on the interiorsurface of the retort. This introduction of the pitch proceedscontinuously as also does the coking operation, and the coked pitchaccumulates in the retort until the capacity of the same is reached,whereupon the feeding of the pitch is shut ofi. Thereafter'the heatingis continuedto complete the coking of all parts of the charge, andfurther kept at a high heat until the coke is completely calcined, thatis, subjected to continuous high heat so that the entire charge isthoroughly coked and in a suitable condition for said uses, thus savinga separate calcining operation.

Thereafter the coke is removed in the usual manner, without interruptingthe con- I ually accumulating a body of pi-tch and simultaneously cokingit and grad-ually and continuously increasing the depth of the cokingbody of pitch by the addition of pitch in liquid form to t e top surfaceof said body, and at the same time proceedingvwith the coking operation.

2. A process of cokin'g pitch, which comprises during the cokingoperation progressively introducing a`coking charge by graduallyaccumulatin a body of itch and simultaneously coking it and gra uallyand -continuously increasing the depth of the coking body of pitch bythe addition of pitch in liquid form tothe top surfacefof said body, andat the same time proceeding with the coking operation, and'then.shutting off the supply of pitch and completing the colti-ng of saidbody.

3. Ay process'of coking pitch, which comprises during thecokingoperation progressively introducing a coking charge by graduallyaccumulating .a Abody of' itch andv simultaneously cokin it and graually and continuously increaslng the depth of the coking-f o pitch infl uid form4 to the top surface of .1 said bodyfand .ali-the Sametimeproceeding with the @king eration, and then shutting Aoff the supply opitch and completing the f pitch by the addition of coking of said body,and thereafter continuing lthe heating of said body until the coke iscalcined.

4. A process of coking pitch, which comprises progressively introducinga coking charge by gradually accumulating a body of. pitchandsimultaneously coking it and continuing the introducing of liquid pitchinto a highly heated coking retort gradually,

in relatively small-quantityat a time, and continuously, and at the sametime proceeding with the coking operation.

5. A process of coking pitch, which comprises progressively introducinga coking charge'by gradually accumulating a body of pitch andsimultaneously coking it andcon'- i tinuing the introducing of 'liquidpitch into a highly heated coking retort gradually, in relatively smallquantity at a time, andcon` tinuously, and 4at the same time proceedingtinuing and completing the coking of' saidv pitch. .A 7. A process ofcoking pitch, which 'comprises progressively -introducing a `cokingpitch and simultaneously coking it, and while the same is being cokedapplying thereon successive quantities'of fluid pitch of relativelysmall depth, and continuing and completing the coking of all of saidpitch.

8. A process of making pitch coke from pitch in a coking chamber of acoking retort oven having heating walls on two opposite sides` of saidchamber provided with combustion flues and havin regenerators below saidcoking chamber an heating walls communicably' connected with' saidcombustionj flues, comprising: introducing pitch into said cokingchamber while said chamber is being highly heated; accumulating saidpitch in a shallow bod on the bottom of said chamber and simu taneouslycoking said body while thereon; adually increasing the dept-h .of saidsha low body by gradual addition of further pitch to the top surface 'ofsaid body and at the same time proceeding with the coking operation.

9. A process of making pitch coke from pitch in a coking chamber of acoking retort oven having heating walls on two opposite vsides of saidchamber provided with combustion filles and having regenerators belowsaid `coking chamber and heating walls communicably connected with saidcombustion flues,

.charge by gradually accumulating` a body of 85 with the cokingoperation, and then shutting A comprising: introducing pitch into saidcoking chamber while said chamber is being highly heated; accumulatingsa'id pitch in a. shallow body on the bottom of said chamber andsinmltaneously coking said body While thereon; gradually increasing thedepth of said shallow bod)v by gradual addition of further pitch to thetop surface of said body and at the same time proceeding with the cokingoperation; then discontinuing the addition of furl her pitch to saidbody and completing the coking ot said body.

' l0. A process ol" making pitch coke -from pitchy material in a cokingchamber of a coking retort oven having heating walls on (u-o oppositesides of' said chamber provided with combustion fines and havingregencralors below said coking chamber and heating walls communicablyconnected with said combustion tlucs, comprising: introducing pilchyn'iaterial into said coking chamber while said chamber is being highlyheated; :weumulating said pitchy material in a shallow body on thebottom of said chamber and simultaneously coking said body while thcre'on; gradually increasing the depth of said shallow body by gradualaddition ot 'further pitchy material to the top surface of said A bodyand at the same time proceeding with the coking operation.

11. A process ot' making pitch coke from 'pitchy material in a cokingchamber of a coking retort oven having heating walls on two oppositesides of said chamber provided with combustion llucs and havingregenerators below said coking vchamber and heating vwalls connnunicablyconnected with said ccmbustion lines, comprising: introducingr pitchymaterial into said `coking chamber while said chamber is being highlyheated; accumulating said pitchy material in a shallow body on thebottom of said chamber and simultaneously coking said body whilethereon; gradually increasing the depth of said shallow body bygradualaddition of further pitchy material to the top surface of said body andat the same time proceeding with the 'coking operation; thendiscontinuing the addition of further pitchy material to said body andcompleting the eoking of said body.

12. A process ot' making pitch coke from pitchy material in a cokingchamber of a coking retort oven, comprising: introducing pitchy materialinto said coking chamber while said chamber is being highly heated;:accumulating said pitchy material in a shallow body on the bottom oisaid chamber and simultaneously coking said body whilev therelon;gradually increasingthe depth of said shallow body by gradual additionof further pin-hy material to the .top surface of said body and atthe'sanie time proceeding with the' coking operation.

13. A process of making pitch coke 'from pitchy material in a cokingchamber of a coki ng retort oven, comprising: introducing pilchymaterial into said coking chamber while said chamber is being highlyheated; accunmlating said pitchy material in a shallow body on thebottom of said chamber and simultaneously coking said body whilethereon; g 'adually increasing the depth of said shallow body by gradualaddition ot' :furthery pitchy material to the top surface ot' said bodyand at the same time proceeding with the coking operation; thendiscontinuing the addition of 'further pitchy material to said body andcompleting the coking of said body.

HEINRICH KoPPERs.

